This invention relates to an on-demand, multiple step fluoroscope control assembly. The invention serves to curtail needless irradiation of patients and operators during fluoroscopic exams.
During a fluoroscopic exam, a continuous, intermittent, or pulsed X-ray beam is used to view an organ or other body part in real time. The live images are displayed on a computer screen or television monitor. Fluoroscopy is most often used to view the upper and lower GI tracts, and during common medical/surgical procedures including cardiac catheterization, angiography, angioplasty, urinary/biliary stone removal, various needle-biopsies, and placement of catheters, stents, and filters.
Fluoroscopy and CT scans account today for the bulk of the doses received by patients from medical x-rays. Accumulated exposure to medical x-rays is a necessary causal co-actor in over half of the fatal cases of cancer and ischemic heart disease (IHD) in the United States. These two diseases account for over a million deaths per year in the USA.
Modern fluoroscopes have features designed to limit needless exposure radiation. Such features include the capability for last-image-hold (“freeze-frame”), which permits physicians to view and discuss an image during a procedure, without continuing to irradiate the patient. Other important features include display capability to show the operator the dose-rate per minute, the duration of exposure, and the accumulated skin-dose to the patient in “real-time” (during the procedure), and to record such doses.
Other ways to reduce x-ray exposure without compromising a procedure are more directly tied to the operator. For example, the fluoroscope is typically activated using a conventional foot switch or “fluoro pedal.” In many cases, during fluoroscopic exams the operator simply forgets to remove his/her foot from the pedal while recording information in the patient file or performing other tasks incidental to the exam. In an effort to alleviate this problem, one prior art control device described in U.S. Pat. No. 5,091,926 is head-activated such that the fluoroscope is intended to function only when the operator is viewing the monitor. The device utilizes an infrared transmitter worn by the operator and an infrared receiver located on fluoroscope monitor. The object of this device is to eliminate the requirement of the foot switch in operating the fluoroscope x-ray and monitor. Replacing the foot switch, however, does not effectively prevent the inadvertent irradiation of patients. For example, the transmitter of the prior art device may be improperly positioned on the head or may become misadjusted during a procedure and accidentally directed towards the monitor.
The control device described in the '926 Patent, like the conventional fluoro pedal, provides only a single-step activation means for controlling operation of the fluoroscope. As such, operators using this device are likely to continue needlessly irradiating patients.